Warp stop mechanism for looms



July 318, 1944. J. H. BURGESS ET AL v WARP STOP MECHANISM FOR LOOMS Filed Feb.- 2, 1944- J/ms Ga Patented July 18, 1944 UNITED STATES PATENT OFFICE 7 2,353,644 WARP STOP MECHANISM FOR LOOMS James H. Burgess, Marion, and Garrett Fender, Nebo, N. C.

Application February 2, 1944, Serial No.-520,-736 2 Claims. (01.139-365) This invention relates to a mechanical warp stop mechanism for looms of that type wherein the detector bar has at detecting movement transversely of the loom.

In warp stop mechanisms of the type indicated, the detector bar is usually associated with a detector bar holder which is held in fixed position, while the detector bar itself is giving a detecting movement transversely of the loom, and both the detector bar and the detector bar holder are provided with a series of teeth. It is usual in this general type of warp stop mechanisms to provide drop wires having elongated slots through which the detector bar and detector bar holder extend, and by which the drop wires are guided in their movement when released by a warp thread. When the drop wire is released by a too slack or broken warp thread, it should engage between the teeth of the detector bar holder, and the similar teeth of the detector bar, whereby the latter is arrested in its transverse movement and loom stoppage is effected by conventional means, not shown.

In conventional warp stop motions of this kind, the detector bar has heretofore been provided with a straight edge on its bottom which slides in the bottom of the slot in the detector bar holder and lint and other matter has been accustomed to collect between the bottom of the detector bar and the detector bar holder, thus raising the detector bar to a point where, when a drop wire is allowedto become lowered, it will not engage between the notches on the detector bar and the notches of the detector bar holder, thus resulting in the loom not stopping as it should and the weaving of imperfect cloth on the loom.

It is an object of this invention to provide a detector bar in warp stop motions having a series of teeth on its lower edge which serve to gradually move the lint and other foreign matter towards and out of one end of the detector bar holder.

It is another object of this invention to provide a detector bar having its teeth rounded at their upper end, so that when a drop wire is allowed to become lowered by a slack warp thread or a broken warp thread, it will fall down between the teeth in the detector bar and to a point low enough to where it will be engaged by both the detector bar and the detector bar holder to stop the loom.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds, when taken in connection with the accompanying drawing, in which:

Figure 1 is an isometric view of one end of a mechanical warp stop mechanism showing my invention associated therewith;

Figur 2 is a side elevation of a portion of a mechanical warp stop mechanism showing my detector bar not only having teeth on its lower edge portion for expelling lint from the groove in the detector bar holder, but also having its teeth rounded on their upper surfaces for guiding the drop wires down into the spaces between the teeth on the detector bar and to a position between the teeth or projections on the detector bar holder;

Figure 3 is a transverse vertical sectional view taken along the line-3+3 in Figure 2;

, Figure 4' is an elevation of a modified form of our detector bar.

The warp stop mechanism-with which the present invention is associated is of the type wherein the detector bar has teeth on its upper edge and is given a detecting movement transversely of the loom, while the detector bar holder is a fixed element having teeth, and associated with the detector bar, and the detector bar holder is a series of drop wires which are normally supported by the warp threads during weaving, but which, when a warp thread breaks or becomes too slack, drop into engagement with the detector bar and detector bar holder and arrest movement of the detector bar. The means for arresting the loom operation on the occurrence of a warp fault is not herein shown, because it forms no essential part of the present invention, which is more particularly concerned with the particular character of the detector bar.

In the drawing, the support HI, which is usually provided at each side of the loom serves as a means for sustaining th operating parts of the stop motion. The supports 10, only one of which is shown, are provided with an opening into which-extends the detector bar holder II. The detector bar holder comprises vertically disposed plates l2 and I3 which have secured between their lower inner surfaces a spacer bar I l, and in the space between the detector bar holder members [2 and l3 is a detector bar It. Detector bar holder H, whether there be one or more, may be suitably secured to the supports ID by means of a bolt I6, which may pass through a slot I! formed in the laterally extending portion of the detector bar H5. The lateral extension of the detector bar it may be utilized as a means for associating the detector bar with mechanisms for imparting movement transversely of the loom, but since details of such mechanism form no part of the present invention, they are not herein shown.

The detector bar holders l2 and I3 are each provided with teeth 18 which are herein shown as separated by a space [9, and each tooth IS in the detector bar holder members is shown as of general rectangular form. Similarly the detector bar I is provided with teeth 20, and such teeth 20 are, as indicated in the drawing, spaced apart in a manner similar to the teeth in the detector bar holder, but the upwardly extending teeth of the detector bar project slightly above the top surfaces of the teeth of the detector bar holder, the result being that should a drop wire be released by a broken or too slack warp thread,

it may drop upon the top surface of the teeth of V the detector bar holder and on the reciprocating movement of the detector bar, it will be moved into engagementbetween the teeth of the detector bar holder and thereby eil'ect stoppage of the detector bar and arrest loom operation.

Any conventional drop wire such as indicated by reference character may be employed which is a conventional drop wire having a slot 26 therein, much longer in length than the overall height of the detector bar holder and the detector bar, and this drop wire has a slot or hole 21 through which an end of yarn 28 is adapted to pass, so that when the yarn has suflicient tautness therein and is not parted, it will hold the drop wire in the position shown in the drawing; however, if the yarn 28 should part or become too slack, it will allow lowering of the drop wire 25 and allow it tobecome disposed between the teeth of the detector bar and the teeth of the detector bar holder, and result in stoppage of the loom.

The structure thus far described is conventional, but such conventional structure has heretofore not operated properly at all times for the reason that lint and other foreign particles find their way down between the detector bar and the detector bar holder and become lodged in the bottom of the slot formed by the members l2, I3, and I 4, and thus in time causes the detector bar to be raised above its normal operation position, and thus resulting in failure of the dropping of adrop wire to cause stoppage of the loom. In order to overcome such defective operation, I have provided in the bottom edge of the detector bar I 5 a plurality of notches 30 having a sloping front wall 3| and a substantially ertically disposed wall 32 so during reciproca- {ion of the detector bar I 5, the lint will enter e notches 30 and will gradually be expelled to t e left in Figures 1 and 2 and out of the end of the slot between the side wall members 12 and I3 of the detector bar holder;

The conventional detector bar having the rectangular teeth 2!] may be provided with the notches 30, or if desired, a new type of teeth 2042 can be provided as shownin Figures 2 and 4. Here teeth 20a are rounded at their upper ends so as to prevent a fallen drop wire from riding on the upper surface of the teeth as might occur in the form of teeth shown in Figure 1.

Ifdesired, the teeth in the lower edge of the detector bar may be shaped so as to more rapidly expel the lint and other foreign particles from between the bars l2 and I3 as illustrated in Figure 4. Here the teeth have a rearwardly sloping wall 35 and another sloping wall 36, the walls 35 and 36 coming to a point so that the lint will more easily pass underneath the lower ends of the teeth and be engaged by the sloping walls 36 to more easily and more quickly expel the lint. This form of invention, although while it will probably expel the lint more rapidly, might wear faster than the form shown in Figures 1 and 2', and the type of notch shown in Figures 1 and 2 is the preferred form of the invention.

It is thus seen that we have provided a detector bar in a mechanical warp stop motion for looms having means for expelling the lint from between the detector bar holder and also having, if desired, rounded upper teeth thereon for assisting in properly placing the drop wires between the teeth on the detector bar holder and the teeth of the detector bar.

In the drawing and specification, there has been set forth a preferred embodiment of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only, and not for the purposes of limitation, the scope of the invention being defined in the claims.

We claim:

1. In a mechanical warp stop motion for looms having a detector bar and a detector bar holder, the detector bar holder having a longitudinal groove therein in which the detector bar is adapted to have reciprocatory movement, and serrations on the lower edge of the detector bar for moving lint and other foreign matter longitudinally of the detector bar holder to expel the lint and other foreign matter from one end of the detector bar, said detector bar and detector bar holder having teeth in their upper edges adapted to be engaged by a fallen drop wire, said serrations being spaced from each other to provide a flat surface between the serrations, one wall of the serrations being at right angles to the longitudinal center of the bar and the other wall of each serration being in a straight line and at an acute angle to the longitudinal center of the bar and bisecting the lower edge of the bar a substantial distance from the right angle sidewall of the next adjacent serration.

2. In a mechanical warp stop motion for looms having a detector bar and a detector bar holder. the detector bar holder having a longitudinal groove therein in which the detector bar is adapted to have reciprocatory movement, and serrations on the lower edge of the detector bar for moving lint and other foreign matter longitudinally of the detector bar holder to expel the lint and other foreign matter from one end of the detector bar, said detector bar and detector bar holder having teeth in their upper edges adapted to be engaged by a fallen drop wire, said serrations being spaced from each other to provide a fiat surface between the serrations, one wall of the serrations being at right angles to the longitudinal center of the bar and the other wall of each serration being in a straight line and at an acute angle to the longitudinal center of the bar and bisecting the lower edge of the bar a substantial distance from the right angle sidewall of the next adjacent serration.

JAMES H. BURGESS. GARRETT W. FENDER. 

